Sheet-metal-blank feeder



H. A. AND R. H. GRIFFITHS.

SHEET METAL BLANK FEEDER.

APPLICATION FILED FEB. 14. 1921.

Patented Oct. 18, 1921.

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' SHEET METAL BLANK FEEDER. APPLICATION FILED FEB. I4, 1921.

1,394,006. Patented 00th 18,1921.

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HARRY ALBERT GRIFFITHS, OF BIRMINGHAM, AND RICHARD HANSON GRIFFITHS, OFSUTTON COLDFIELD, ENGLAND.

1 0 all whom it may concern.

Be it known'that we, HARRY ALBERT GRIF- rirns, residing at 8 Chad road,Edgbaston, in the city of Birmingham, England, and RICHARD HansonGRIFFITHS, residing at Highfield, Sutton Coldfield, in the county of\Varwick, England, subjects of the King of Great Britain and Ireland,have invented certain new and useful Sheet-Metal- Blank Feeders, ofwhich the following is a specification 7 This invention relates tomechanically actuated presses for operating on circular or other sheetmetal blanks, and has for its object to provide improved automaticfeeding mechanisms of the type in which the bottom blank of a stack ofsuperimposed blanks is separated from those above it by means of a knifeor a plurality of knives and subsequently fed to the press tools bygravity or otherwise. V

The invention comprises the employment in conjunction with anoscillatory knife, of

an oscillatory support for the stack of blanks, the support beingadapted to release the bottom blank after the knife has engaged thestack.

The invention also comprises the use of a pair of oscillatory knivesadapted to operate insuccession and herein termed primary and secondaryknives, and the arrangement in conjunction with the sec ondary knife ofan oscillatory support adapted to serve as the sole or principal supportfor the stack of blanks, this support being caused to release the bottomblank after the secondary knife has passed into position for supportingthe superincumbent blanks.

In the accompanying sheets of explanatory drawings:

Figure 1 is a plan and Fig. 2 a front elevation of one form of blankfeeding mechanism constructed in accordance with this invention.

The primary knife a is secured at the upper end of an oscillatoryspindle Z). This knife is in the form of a relatively small disk havinga knife edge and having a portion of its peripheryncut away so that theadjacent portion of the stack of circular sheet metal blanks 0 can reston a support (Z which is also secured to the spindle. The support is inthe form of a circular disk which has .a portion of its periphery outSpecification of Letters Patent.

Patented Oct. 18, 1921.

Application filed February 14, 1921. Serial No. 444,835.

away so that it can leave the blanks. The distance between the upperface of the support and the lower face of the knife is equal to thethickness of a blank. Referring to F ig, l, the support is there shownin engagement with the underside of the stack of blanks. On rotatingtheknife and support in the direction of the arrow, the knife first entersthe stack immediately above the lower blank and lifts the other blanks.After the knife has entered sufficiently far the support leaves thebottom blank, but the latter is not yet free to fall away because it isstill carried by another support to be hereinafter described. Motion isimparted to the primary knife (6 and support (Z by a lever e secured tothe lower end of the spindle b and actuated in one direction by a link fwhich receives motion from another link 5/ connected to any convenientmoving part of the press mechanism. Motion in the return direction maybe effected by a spring h.

Adjacent to the primary knife is arranged the secondary knife z'. Thisconsists of a broad oscillatory blade pivoted at j and actuated by alink is connected to the above mentioned link g,- both knives movetogether. The return motion may be given to the knife i by a spring Z.The disposition of the knife 2' in relation to the knife a. is such (asshown in Fig. 1), that the knife a first enters the stack of blanks andproduces an opening into which the secondary knife 2' can enter. Theknife 7, then separates the stack completely from the bottom blank.

Secured to the knife '5 is the support m. This also consists of a broadblade which normally acts as the main support for the stack of blanks.While the knife 2' is entering the stack, the support m is moving away,and'finally when the knife z is fully in position, the support m isclear of the bottom blank. Meanwhile the support 61 has also moved clearof the bottom blank, and the latter is therefore free to fall away on toan inclined or other table whence it can pass by gravity or otherwise tothe press tools. In the return of the knives, the support m comes intoits active position before the knife z' leaves the blanks. As soon asthe knife 71 is clear of the blanks, the stack falls on to the support mwhich now carries the stack prior to a repetition of the operationsabove described. It will be understood that the vertical distancebetween the knife 2' and support m is equal to or rather greater thanthe thickness of the blank.

Lateral-displacement of the blanks forming the stack is prevented bythree upright guides 12 between which the stack of blanks is free tomove. Usually it is found advantageous to load the stack by a weight 0as shown in Fig. 2. The weight serves to hold the stack firmly on thesupports when the mechanism is operating at high speed.

The invention is capable of'being carried out in a variety of ways.Thus, the oscilla-- anism illustrated the support (Z may be dispensedwith. As a further alternative the knife 11 and support an may bedispensed with in which case two or more knives as a and supports as. dare arranged at suitable positions relatively to the stack of blanks andcaused to act on the stack simultaneously.

The invention is not limited to any particular mechanical details asthese may be varied to meet different requirements.

Having thus described our invention what we claim as new and desire tosecure by Letters Patent is 7 1. In. mechanism for individually feedingsheet metal blanks from a stack to the tools of a press, the combinationof a pair of oscillatory separating tools, a'support arranged inconjunction with one of the tools, and means for actuating theseparating tools and support so that one of the separating tools firstenters the stack of the blanks and forms an aperture between the bottomblank and those above it, and then the second separating tool enters andcompletely separates the bottom blank from the stack, the supportmeanwhile moving and finally allowing the bottom blank to fall away whenthe second separating tool has sufficiently entered the stack to supportthe blanks above it, substantially as described.

2. In mechanisms for individually feeding sheet metal blanks from astack to the tools of a press, the combination of an oscillatory supportfor a stack of blanks, a separating tool arranged in conjunction withthe support, the underside "of'the tool being in a plane which isseparated from that contain ing the upper surface of the support by adistance equal or approigimately equal to the thickness of the blanks,and the mutual arrangement of the separating tool and support being suchthat the one moves into its operative position before the other iswithdrawn from the stack, an additional oscillatory separating tooladapted to produce

